This study will establish the time course of 5HT2 receptor occupancy in human volunteers, utilizing 18F-setoperone and imaging to define the pharmacokinetics of receptor occupancy in normal human brain and to delineate the effects of CP-88,059, and antipsychotic drug with affinity both for serotonin 5HT2 and dopamine D2, on the pharmacokinetics of receptor binding by 18F-setoperone.